I only have one kid, but I am one of 13. (only 4 of us were full blood, and lived together our entire childhood though. the other 9 were all steps, halves, or deceased...) of the four of us...
Oldest brother was very rebellious, and would fight every little thing. So while yes, my dad loved him and they had their good times, he had to be a lot more strict with him. You give an inch, he would take a mile.
I was a very easy kid. When my mom left, I did a lot of the cleaning, cooking, and keeping track of my siblings when I was old enough. (I was 4 when she left) I literally never argued with my dad (in my life, we can only remember 3 arguments with him..) I got privleges (later curfew, allowed to get a driver's license and a job earlier) because I earned them. Although, I was also a 'daddy's girl' from the beginning (even as an infant I preferred him over my mom) so we have always had a special bond...
My younger brother was just lazy, but a good kid. My dad had to make sure to stay on top of him to get things done. He didn't get in much trouble, but he needed a lot more supervision than the others.
My younger sister was a drama Queen. (that's right... capital Q.) and the 'baby' for quite a few years. She always wants everything her way, so feels like she's picked on because she is turned down more often. (Of course, if you are going for 30 things and get turned down for 20 of them, you still get 10... and when the other kids only ask for 5, you still come out on top. but she didn't see it that way... lol)
Yep. very different children, very different parental treatment. But we were all loved, no doubt about that.